Data storage systems generally reserve private storage space on one or more storage devices or drives for storing data used internally and/or privately by certain storage system components, such as a data rebuild component, a file system checking (FSCK) component, and a data deduplication component, among others. Such private storage space is typically reserved for (i) the data rebuild component to implement a “hot spare” drive in the event of a storage drive failure, (ii) the FSCK component for use in offline FSCK recovery operations, and (iii) the data deduplication component for storing identifiers (e.g., hash values) for a stream of data elements received at the storage systems.